HACK: avcodec/rkmppdec: Alloc contig frame buffer when using default …

…get_buffer2

Currently the librga only supports contig buffers.

The default get_buffer2 would use different buffers for planes, so we
need to replace them with contig one to take advantage of RGA 2D accel.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>

libavcodec/rkmppdec.c

@@ -54,6 +54,9 @@ typedef struct {
     AVPacket packet;
     AVBufferRef *frames_ref;
     AVBufferRef *device_ref;
+
+    AVBufferPool *pool;
+    int pool_size;
 } RKMPPDecoder;
 
 typedef struct {
@@ -95,6 +98,9 @@ static int rkmpp_close_decoder(AVCodecContext *avctx)
 
     av_packet_unref(&decoder->packet);
 
+    if (decoder->pool)
+        av_buffer_pool_uninit(&decoder->pool);
+
     av_buffer_unref(&rk_context->decoder_ref);
     return 0;
 }
@@ -442,6 +448,44 @@ static int rkmpp_get_frame(AVCodecContext *avctx, AVFrame *frame, int timeout)
         goto fail;
     }
 
+    // drm_prime does support internal frame allocation.
+    if (avctx->pix_fmt != AV_PIX_FMT_DRM_PRIME) {
+        if (avctx->get_buffer2 != avcodec_default_get_buffer2) {
+            ff_get_buffer(avctx, frame, 0);
+        } else {
+            // the avcodec_default_get_buffer2 would use different
+            // buffers for planes, let's alloc config buffer instead.
+            // TODO: support setting y/u/v address in librga?
+            // TODO: or replace with custom get_buffer2
+            int size = mpp_frame_get_buf_size(mppframe);
+            int hstride = mpp_frame_get_hor_stride(mppframe);
+            int vstride = mpp_frame_get_ver_stride(mppframe);
+
+            if (decoder->pool_size != size) {
+                if (decoder->pool)
+                    av_buffer_pool_uninit(&decoder->pool);
+
+                decoder->pool = av_buffer_pool_init(size, NULL);
+                decoder->pool_size = size;
+            }
+
+            // free old buffers
+            av_buffer_unref(&frame->buf[0]);
+            av_buffer_unref(&frame->buf[1]);
+            av_buffer_unref(&frame->buf[2]);
+
+            frame->buf[0] = av_buffer_pool_get(decoder->pool);
+
+            frame->linesize[0] = hstride;
+            frame->linesize[1] = hstride / 2;
+            frame->linesize[2] = hstride / 2;
+
+            frame->data[0] = frame->buf[0]->data;
+            frame->data[1] = frame->data[0] + hstride * vstride;
+            frame->data[2] = frame->data[1] + hstride * vstride / 4;
+        }
+    }
+
     // setup general frame fields
     frame->format           = avctx->pix_fmt;
     frame->width            = mpp_frame_get_width(mppframe);